1. Field of the Invention
The present invention refers to a turning device, especially to a turning device for paper, of the type used e.g. in paper handling systems.
Paper handling systems making use of a turning device are primarily used by large enterprises, banks, insurance companies, service-rendering enterprises, etc. In these enterprises, the paper handling systems serve to process large amounts of paper, such as invoices, reminders, statements of account and the like.
2. Description of Prior Art
These paper handling systems use different devices for turning the paper which are known from the prior art.
A first device used according to the prior art for the purpose of turning paper turns the paper in a helical movement during transport. This kind of turning is effected by guiding the paper helically and is also referred to as helical turning. A disadvantage of such helical turning of the paper during transport is to be seen in the fact that long paths are necessary because the paper is wound during turning. When a thick object, such as a stack of paper or a pack, is to be processed, the turning path must be dimensioned in accordance with the admissible winding. In the case of loose, thick packs the act of winding results in slipping or displacement of the object to be turned in itself and this may make further processing more difficult or prevent such further processing. Another disadvantage is that, due the long transport paths, several objects will move along the turning path in most cases, and this may cause collisions in the turning path when stagnation occurs during processing in the follow-up device, since the turning path is provided with permanent drives and can therefore not be stopped within a sufficiently short period of time. Still another problem arises when mixed processing of individual sheets and of thick packs consisting of several sheets is carried out, since guiding problems will then arise due to the resultant vertical movement of the transport belts so that, in the case of a narrow sequence, the thinner object located between a preceding thicker object and a subsequent thicker object is not guided firmly enough and will therefore slip between the conveyor belts. This type of turning path is also disadvantageous insofar as it does not offer the possibility of selecting between turning and non-turning. If the way in which the paper is processed does not require any turning operation, the turning path will have to be replaced by a feed-through path in this case, i.e. it will be necessary to remove the turning device from the paper handling system and to install the feed-through path in the paper handling system.
Another device used according to the prior art is a turning wheel comprising a plurality of trays. In such a turning wheel several trays, which serve to accommodate the material to be turned, are normally arranged such that they extend in a starshaped mode of arrangement towards the centre of rotation of the turning wheel. The disadvantage of this turning wheel is that a large turning diameter is required, which, in turn, results in a large overall size. Another disadvantage is that, when the turning wheel is used, a large lateral displacement between the input and the output of the turning wheel will occur when the material is being turned, and this will, in turn, enlarge the width of the overall size. Still another disadvantage is that, due to the large turning circle of the turning wheel, high moments of inertia have to be overcome during acceleration and deceleration of the turning wheel, and this necessitates a high driving power. A further disadvantage is that this kind of turning device does not offer the possibility of selecting between turning and non-turning either. If the way in which the paper is processed does not require any turning operation, it will again be necessary to replace the turning wheel by a feed-through path with deflection points.
AT 310639 refers to a turning device for turning clay bodies of the type shown in detail on the basis of FIGS. 1 and 2 thereof. From AT 310639 it is known to provide a turning device having provided therein a reception tray into which a clay body can be introduced such that its axis of rotation substantially coincides with the axis of rotation of the reception tray. Furthermore, rollers are provided, which serve to introduce the clay body in and to remove it from the turning device.
FR 2161320 refers to a turning device for turning plate-shaped elements, which comprises a reception tray into which the plates are introduced, the axis of rotation of the plates essentially coinciding with the axis of rotation of the reception tray also in this case. Furthermore, feed means and removal means are provided for feeding the plates to be turned to the turning device and for removing the turned plates from the turning device.
DE 37 03 951 A1 refers to a turning device for stacks of paper, which is arranged between a feed means and a discharge means. Two pressure jaws for holding the stack of paper are provided, said pressure jaws being floatingly supported on guide means and having associated therewith defined stop means so that the respective lower pressure jaw will always be adjusted automatically to the feed and discharge level of the feed means of the discharge means, respectively.